A rotorcraft may include a removable equipment support that is suitable for carrying a winch, for example.
A first type of equipment support comprises a support arm fastened at a single point to a structure of the aircraft. The single point is designed to take up forces, and may be referred to as a “take-up” point. That first type of support also includes supports provided with a support arm that is fastened to a single zone of the structure by a plate.
The support arm may optionally be hinged to make it easier to maneuver the equipment being carried.
Although equipment supports of the first type, i.e. supports that are fastened to a single take-up point, are attractive, they present the drawback of being capable of supporting only relatively small forces.
The take-up point of the arm on the structure must necessarily be situated on a load-carrying structure of the aircraft. Such a load-carrying structure is generally a carrier frame contained in an elevation plane of the aircraft and located beside an opening in the fuselage of the aircraft, through which opening an operator may handle the supported equipment, for example.
Under such circumstances, the support arm of the equipment support extends over a considerable distance in order to reach the take-up point. As a result, there is a considerable lever arm that limits the load that the equipment support is capable of supporting.
Furthermore, the carrier frame needs to be strongly reinforced at the take-up point for the support arm.
Document U.S. Pat. No. 4,566,659 presents a support of the first type that is hinged so as to be capable of being moved in an elevation plane of the aircraft.
It is possible to envisage using a support of a second type that is fastened to two take-up points of the structure of the aircraft. Nevertheless, a support that is fastened at two points does not appear to be capable of supporting relatively large forces. In addition, the structure of an aircraft is subjected to aerodynamic forces in flight that tend to deform it. Any such deformation of the structure would appear to be incompatible with a support that is fastened to two take-up points.
Thus, the state of the art presents in contrast an equipment support of a third type that is fastened to the structure not via two take-up points but rather via three, mainly two take-up points in a top portion above a lateral opening in the fuselage and one take-up point in a bottom portion situated beneath said opening or on a carrier frame of the load-carrying structure of the aircraft.
Document U.S. Pat. No. 6,488,236 presents a support of the third type having an arm connected to a fastener shaft, a bottom portion of the shaft being secured at a first take-up point to a floor while a top portion of the shaft is secured at a second take-up point to a ceiling. Furthermore, the support is provided with a rod that is fastened to a third take-up point.
That architecture using three take-up points is advantageous in that it enables heavy loads to be supported. Nevertheless, it will be understood that it is bulky and heavy, which is penalizing in an aviation application.
Document GB 2 157 647 describes a device having a horizontal plate that co-operates with a vertical plate for carrying loads.
Document U.S. Pat. No. 3,764,105 is remote from the invention in that it presents a device for enabling an aircraft wheel to be changed.
Document U.S. Pat. No. 6,126,113 shows a helicopter provided with a honeycomb structure.
Document U.S. Pat. No. 5,540,402 presents a beam carrying a net.
Document U.S. Pat. No. 2,953,330 presents a rectangular box structure suspended from an aircraft.